oj.uz

Submission #27154

# Submission time Handle Problem Language Result Execution time Memory
27154 2017-07-09T17:05:01 Z bill_kondo Pipes (CEOI15_pipes) C++14
50 / 100
 2413 ms 28204 KB 
#include "bits/stdc++.h"
using namespace std;

#define pb push_back
#define debug(args...) fprintf(stderr,args)
#define FOR(i,a,b) for(int i = a; i <= b; ++i)
#define REP(i,a,b) for(int i = a; i >= b; --i)

typedef long long ll;
typedef pair<int,int>pii;

const int maxn = 1e5 + 10;

int n, m;
map<pii,int>cnt;

struct dsu{
	int par[maxn];
	int sz[maxn];

	void init(){
		FOR(i,1,n){
			par[i] = i;
			sz[i] = 1;
		}
	}

	int root(int v){
		if(par[v] == v) return v;
		return root(par[v]);
	}

	void merge(int x, int y){
		x = root(x);
		y = root(y);
		if(x == y) return;
		if(sz[y] > sz[x]) swap(x,y);
		par[y] = x;
		sz[x] += sz[y];
	}
} T[2];

void add(int u, int v){
	if(u > v) swap(u,v);
	pii p = pii(u,v);
	++cnt[p];
}

int e(int u, int v){
	if(u > v) swap(u,v);
	pii p = pii(u,v);
	return cnt[p];
}

vector<int>adj[maxn];

int h[maxn], low[maxn], cur;
bool mrk[maxn];

void dfs(int v, int par){
	mrk[v] = true;
	low[v] = h[v] = ++cur;
	for(int i = 0; i < adj[v].size(); ++i){
		int u = adj[v][i];
		if(u == par) continue;
		if(!mrk[u]){
			dfs(u,v);
			low[v] = min(low[v],low[u]);
			if(low[u] > h[v] && e(u,v) == 1) printf("%d %d\n",u,v);
		}
		else low[v] = min(low[v],h[u]);
	}
}

void tarjan(){
	FOR(i,1,n)
		if(!mrk[i])
			dfs(i,-1);
}

int main(){
	scanf("%d%d",&n,&m);
	T[0].init();
	T[1].init();

	FOR(i,1,m){
		int a, b;
		scanf("%d%d",&a,&b);
		if(T[0].root(a) != T[0].root(b)){	
			adj[a].pb(b);
			adj[b].pb(a);
			T[0].merge(a,b);
			add(a,b);
		}
		else if(T[1].root(a) != T[1].root(b)){
			adj[a].pb(b);
			adj[b].pb(a);
			T[1].merge(a,b);
			add(a,b);
		}
	}
	tarjan();
	return 0;
}

Compilation message

pipes.cpp: In function 'void dfs(int, int)':
pipes.cpp:63:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < adj[v].size(); ++i){
                 ~~^~~~~~~~~~~~~~~
pipes.cpp: In function 'int main()':
pipes.cpp:82:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
  ~~~~~^~~~~~~~~~~~~~
pipes.cpp:88:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&a,&b);
   ~~~~~^~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2688 KB Output is correct
2 Correct 4 ms 2688 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 3840 KB Output is correct
2 Correct 11 ms 3584 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 146 ms 3632 KB Output is correct
2 Correct 142 ms 3340 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 261 ms 5108 KB Output is correct
2 Correct 304 ms 4600 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 486 ms 8796 KB Output is correct
2 Correct 432 ms 8128 KB Output is correct

Subtask #6
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 841 ms 20640 KB Memory limit exceeded (if you are sure your verdict is not MLE, please contact us)
2 Halted 0 ms 0 KB -

Subtask #7
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 1204 ms 23408 KB Memory limit exceeded (if you are sure your verdict is not MLE, please contact us)
2 Halted 0 ms 0 KB -

Subtask #8
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 1583 ms 28132 KB Memory limit exceeded (if you are sure your verdict is not MLE, please contact us)
2 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 1892 ms 28204 KB Memory limit exceeded (if you are sure your verdict is not MLE, please contact us)
2 Halted 0 ms 0 KB -

Subtask #10
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 2413 ms 26920 KB Memory limit exceeded (if you are sure your verdict is not MLE, please contact us)
2 Halted 0 ms 0 KB -